Table 3.

Changes in the vascular resistance in various organs are calculated for a normal person (while resting and during exercise) and for a hypertensive patient (resting and during fever)

			Normotensive person				Older hypertensive patient with a large allostatic load
			During rest (ΔP = 97 mmHg)		Exercise (ΔP = 100 mmHg)		During rest (ΔP = 110 mmHg)		Fever (ΔP = 110 mmHg)
Circulatory circuit	Organs	Mass	Blood flow	Vascular resistance	Blood flow	Vascular resistance	Blood flow	Vascular resistance	Blood flow	Vascular resistance
		kg	l/min	MPas/m3	l/min	MPas/m3	l/min	MPas/m3	l/min	MPas/m3
Peripheral circuit (data in grey cells from the ref. 34)	Liver	2.6	1.50	517.33	1.50	533.33	1.50	586.67	1.50	586.67
	Kidneys	0.3	1.26	615.87	1.26	634.92	1.26	698.41	1.26	698.41
	Brain	1.4	0.75	1034.67	0.75	1066.67	0.75	1173.33	0.75	1173.33
	Skin	3.6	0.46	1676.03	0.46	1727.86	0.46	1900.65	2.50	352.00
	Skeletal muscle	31	0.84	923.81	8.00	100.00	0.84	1047.62	2.00	440.00
	Heart muscle	0.3	0.25	3104.00	0.75	1066.67	0.25	3520.00	0.75	1173.33
	Rest of the body	23.8	0.34	2302.67	0.34	2373.89	0.34	2611.28	0.34	2611.28
	Whole body	63	5.40	143.70	13.06	61.26	5.40	162.96	9.10	96.74
Pulmonary circuit (ΔP = 9 mmHg)		1.3	5.40	13.33	13.06	5.51	5.40	13.33	9.10	7.91

The cardiac output adapts to the ever changing integrated resistance of all vessels. Calculated resistance values suggest that organs adapt their vascular resistance to maintain normal perfusion rates and hydrostatic capillary pressure. This means that increased allostatic load can lead to hypertension that will be compensated by increased resistance. This builds up the pressure reserve in the arterial tree that might improve acute physical responses and accelerate atherosclerosis. Pulmonary resistance needs to be protected from vasoconstrictors in the systemic circulation in febrile patients with allostatic loads. Otherwise, the pulmonary circuit might become the circulatory bottleneck, leading to compromised perfusion patterns and blood oxygenation in lungs